Mark Nielsen defeated Woong Sun Jun 7-6 6-4 in the Japan F3 qualifying round on carpet. The upset overturned the form book — Woong Sun Jun came in leading the head-to-head 1–0. Mark Nielsen claimed a first win over Woong Sun Jun in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2004-04-26 | Japan F3 | R32 | hard | Woong Sun Jun | 7-6(5) 3-6 6-4 |
Averages over each player's completed matches in the selected window (2 vs 14). ATP, WTA & Challenger.
Each player's serve crossed against the other's return, converted to expected hold of serve. Recent completed matches, ATP, WTA & Challenger. About